Process of making phenylglycin salts.



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WILHELM BEHAGHEL AND GUSTAV KURT SCHUMANN, OF LUDWIGS-HAFEN-ON-THE'RHTNE, GERMANY, 'ASSIGNORS TO BADISOHE ANI- LIN & SODAFABRIK, OF LUDWIGSH AFEN-ON-THE-RH lNE, GERMANY,

A CORPORATION.

PROCESS OF MAKING PHEN YLGLYCEN SALTS,

Specification of Letters Patent.

'ratented April 17, 1906.

Application filed September 21. 1905. Serial No. 279,545.

1'0 all whom it may concern:

Be it known that we, WILnELM BEHAGHEL, a subject of the Grand Duke ofBaden,'and GUSTAV KURT SCHUMANN, a subject of the King of Saxony,doctors of philosophy and chemists, residing at Ludwigshafen-on-the-Rhine, in the Kingdom of Bavaria, German Empire, have invented new anduseful Improvements in the Manufacture of Phenylglycin Salts, of whichthe following is a specification.

The usual method hitherto employed for the production of phenylglycinsalts. consists in reacting upon 0 loracetic acid with an excess ofamlin, making the reaction mixture alkaline, and then distilling off theexcess of anilin by means of steam and then filtering off the anilid,which is always formed at the same time, the (phenylglycin-being setfree by means of aci volving a separate process for working up thisanilin. The phenylglycin is, however, to a considerable extent solubleinWater, and

: consequently the solution has had either to be evaporated 0r extractedwith ether in order to obtain the part which had remained in solution.The method of directly evaporating the alkaline solution which isobtained after filtering ofi the anilid does not lead to the desiredeffect, since all the chlorin which comes from the chloracetic acid'iscontained in this solution, and consequently a mixture of phenylglycinsalt and alkali chlorid results.

We have now discovered that phenylglvcin salts can be prepared much moreeasi y and good yields be obtained by converting the phenylglycin atfirst formed into the anilid, separating this, and then saponifying it.

The best method of carrying out our invention consists in heating,preferably in cacao, the reaction mixture containing phenylglycinobtained by treating chloracetic acid with an excess of anilin andcontinuing this heatin until water ceases to be given off. The mixtureis then made alkaline, the excess of anilin is distilled oil with steam,and the residual liquid is allowed to cool, whereupon the anilid, whichis practically insoluble in cold and precipitated, thus in-- {water, isfiltered oil and washed and can thus be obtained free from inorganic'mpurities. The anilid can be completely saponified by heating it with asolution of one molecular proportion of caustic alkali, so that byevaporating such a solution the pure phenylglycin salt can be obtained.

The following are examples of ways In which our invention can be carriedinto practical effect; but our invention is not confined to theseexamples. The parts are by weight.

Example 1: Heat together for three (3) hours at a temperature ofonehundred (100) degrees centigrade one (1) part of chloracetic acid andfive (5) parts of anilinand then raise the temperature to one hundredand twenty (120) degrees centigrade and continue' heating in vacuo atthis tern erature until water ceases to distil over. T ien add sodiumcarbonate until the excess of anilin is set free and distil off thiswith steam. On cooling the phenylglycin anilid solidifies to acrystalline mass. Filter this off, wash with water, and then heat it inan autoclave with a solution of one (1) molecular proportion of causticalkali. When the saponification is complete, distil oil the anilin whichhas been split off and evaporate the resulting solution to dryness,preferably "in vacuo.

Example .2: Boiltcgether for three (3) hours in areflux apparatus one(1) part of chloracetic acid, two (2) parts of water, and five (5) partsof anilin and then distil oil the wa tcr'i'rt cacao, finally raising thetemperature to from one hundred and twenty (120) to one hundred andforty (140) degrees Centigrade, maintaining this temperature until waterceases t be distilled over. cess of caustic-soda solution, separate theaqueous layer from. the anilin in which the anilid is contained, add one(1) molecular proportion of caustic-soda solution to this mixture, andthen heat at a temperature of about one hundred and forty (140) degreescentigrade in an autoclave provided with a stirring apparatus. When thesaponification is complete, distil oil' the excess of anilin and evaorate to dryness the solution of the phenylg ycin salt.

Add a slight excessof am Now, What We ciaim is I The process ofmakingphenylgl cin salt set our handein the presence of two subscrib--byfreecth? 011 ch oracetlc acid -w1t an exing Witnesses.

WILHELM BEHAGHEL.

in until the phenylglyein'is con- GUSTAV KURT SCHUMANN. 5vverted intoits anilid, separatin this anilid Witnesses:

and saponifying it with caustic a kali. J. ALEO. LLOYD,

In testimony whereof We have hereunto Jos. H. LEUTE.

